Feeding ratio of hydrogen to coal is important parameter to design the plant of hydrogasification process, because it determines directly volume and diameter of equipments in the process anit relates to plant cost, running cost and its thermal efficiency. There were some papers showing that the ratio effect on the conversion of coal to methan and BTX, however there also were some objections against this observation. An apparatus that can gasify a coal in a reactor having a definite volume has been made and the details of this effect was investigated. It seems that this effect was the result of competition between two kind of reactions occured around volatile matter, decomposing into gas and condsnsating into liquid droplet.